It’s no secret that recent graduates with degrees in the liberal arts are out-earned by most of their classmates. But in the long run, they catch up to at least some of their peers.

Humanities and social sciences students, for example, make 84% as much as professional and pre-professional students like nurses and criminologists at ages 21-25—but they pull in about $2,000 more during their peak earning years from 56-60 ($66,185 compared with $64,149).

Those numbers come courtesy of a new report by the Association of American Colleges and Universities, a group that advocates for a broad-based undergraduate liberal-arts education. The AAC&U studied more than 3 million responses to the U.S. Census Bureau’s 2010 and 2011 American Community Survey, and earnings are reported in 2011 dollars.

“The perception of a lot of people is if you major in business, you’re guaranteed to do well and if you major in English, you’re guaranteed not to do well,” says Debra Humphries, vice president for policy and public engagement at AAC&U. But in the long term, those lines blur.

“It’s the difference between a 50-yard dash and a marathon,” says Katharine Brooks, executive director for personal and career development at Wake Forest University. It might take liberal arts students a little longer to settle on a particular career path than it does graduates who were gunning for accounting or nursing jobs from freshman year, but they often take similar jobs in the end, including in finance, education and social work.

Another reason liberal arts graduates end up closing the gap with pre-professional students: Forty percent of humanities and social sciences students ultimately go on to graduate school, with 9% headed to professional degree programs like M.B.A.s and law school, according to the AAC&U report, while just 30% of professional and pre-professional students do (and only 4% get professional degrees).

Still, English majors might not want to jump for joy, at least not if they’re standing next to engineers.

By the time they hit their peak earning years between 56 and 60, no matter whether they stopped after four years of college or continued on to master’s or doctoral programs, liberal arts students can expect median annual pay of $66,185 – just two-thirds of the income that engineering graduates see. (That’s not much better than when they were back in their early 20s, earning about 63% as much.)

And even though they brought home more bacon than physical, natural sciences and math students right out of school, humanities and social sciences graduates were making just 76% as much as lab rats by their late 50s.

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